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ShapeElongation


Header:FIL.h
Namespace:fil

Computes the elongation factor of a shape (perfect circle has minimal elongation equal 1.0).

Syntax

C++
C#
 
void fil::ShapeElongation
(
	const fil::Path& inShape,
	float& outElongation
)

Parameters

Name Type Default Description
inShape const Path&
outElongation float&

Description

Elongation is a measure of how long the shape is in relation to its width. The perfect circle has the minimal elongation equal to 1.0, while the upper bound doesn't exist. The operation internally approximates the shape with an ellipse, and then computes the result as: Where L denotes the longer axis of the approximating ellipse, and S denotes the shorter one.

Note that if the input path is not a valid shape (i.e. it has at least one self-intersection), the computation may lead to results that are not intuitive.

Examples

Elongation of the sample shape equals to 3.283.

Elongation of the sample shape equals to 1.001.

Errors

List of possible exceptions:

Error type Description
DomainError Degenerate shape on input in ShapeElongation.
DomainError Open path on input in ShapeElongation.

See Also

  • ShapeCircularity – Computes the area of a shape divided by the area of a circle having the same feature.
  • RegionElongation – Computes the elongation factor of a region ( perfect circle has minimal elongation equal 1.0 ).